Phase-stabilized ammonium nitrate prills and related products and methods

Abstract

Phase-stabilized ammonium nitrate (PSAN) prill including ammonium nitrate and a potassium salt are provided. The PSAN prill can be explosive grade and low density. The PSAN prill may include a porosity enhancing agent such as an interfacial surface modifier or a pore former. Methods of preparing the PSAN prill and related emulsions are also provided.

The invention claimed is: 
     
       1. A phase-stabilized ammonium nitrate (PSAN) prill comprising:
 ammonium nitrate; 
 a porosity enhancing agent; and 
 a potassium salt, wherein the PSAN prill comprises from 2.1 mole percent (mol %) to 5 mol % potassium ions of the potassium salt based on the ammonium ions of the ammonium nitrate, wherein the potassium salt comprises at least one of potassium hydroxide, potassium nitrate, potassium sulfate, potassium hydrogen sulfate, potassium carbonate, or potassium hydrogen carbonate; 
 wherein the PSAN prill is explosive grade and has a bulk density less than 0.9 kg/L, and 
 wherein upon thermal cycling the PSAN prill 20 times, wherein one cycle comprises four hours at 15° C. followed by four hours at 45° C., an average crush strength of the thermal cycled PSAN prill is greater than an average crush strength of non-thermal cycled control PSAN prill. 
 
     
     
       2. The PSAN prill of  claim 1 , wherein the mol % of the potassium ions based on the ammonium ions is from 3 mol % to 5 mol %. 
     
     
       3. The PSAN prill of  claim 1 , wherein the PSAN prill has at least about 5.7% porosity. 
     
     
       4. The PSAN prill of  claim 1 , wherein the porosity enhancing agent comprises an interfacial surface modifier, a pore former, or both. 
     
     
       5. The PSAN prill of  claim 4 , wherein the interfacial surface modifier comprises at least one of an alkyl sultanate polymer, an alkaline metal salt of naphthalenesulfonic acid, an alkaline metal salt of alkyl sulfonic acid, an alkaline metal salt of polystyrene sulfonic acid, or aluminum sulfate hydrate. 
     
     
       6. The PSAN prill of  claim 4 , wherein the concentration of the interfacial surface modifier is from 400 ppm to 4,000 ppm. 
     
     
       7. The PSAN prill of  claim 1 , wherein the potassium salt comprises at least one of potassium hydroxide, potassium nitrate, or potassium sulfate. 
     
     
       8. The PSAN prill of  claim 1 , wherein the PSAN prill substantially lacks a 32° C. crystalline phase change. 
     
     
       9. The PSAN prill of  claim 1 , wherein the PSAN prill substantially lacks an 84° C. crystalline phase change. 
     
     
       10. The PSAN prill of  claim 1 , wherein upon thermal cycling the PSAN prill 50 times, wherein one cycle comprises four hours at 15° C. followed by four hours at 45° C., the thermal cycled PSAN prill has an average crush strength greater than 0.4 kg. 
     
     
       11. The PSAN prill of  claim 1 , wherein the shelf life of the PSAN prill is at least two months at an average daytime ambient temperature from about 30° C. to about 50° C. and an average night time temperature of about 10° C. to about 30° C. 
     
     
       12. The PSAN prill of  claim 1 , wherein crystal domains of the PSAN prill are more tightly packed and more uniform than the crystal domains of an explosive grade ammonium nitrate prill devoid of potassium and having similar density and porosity to the PSAN prill. 
     
     
       13. The PSAN prill of  claim 1 , wherein the PSAN prill comprises potassium uniformly distributed throughout the prill.